1. Field of the Invention
The present invention relates to a mass spectroscopy device for use in a process of performing mass spectroscopy of a material to be analyzed (analyte) which is contained in a specimen arranged in contact with the mass spectroscopy device by irradiating the specimen with light so as to desorb the analyte from a surface of the mass spectroscopy device. The present invention also relates to a mass spectroscopy system having the above mass spectroscopy device. The present invention further relates to a microstructure which uses optical resonance in an optical resonator.
2. Description of the Related Art
The mass spectroscopy is used for identifying materials. In a known technique of performing mass spectroscopy of an analyte which is contained in a specimen, the specimen is arranged in contact with a mass spectroscopy device, and irradiated with measurement light (i.e., light applied to the mass spectroscopy device for measurement) so as to desorb the analyte from a surface of the mass spectroscopy device for the mass spectroscopy. Then, the desorbed analyte is identified by detecting the mass of particles constituting the desorbed analyte, for example, by the time-of-flight mass spectroscopy (TOF-MS). In the TOF-MS, the particles constituting the desorbed analyte are accelerated so that the particles fly over a predetermined distance, and the time of the flight (in which the mass of the particles are reflected) is detected.
In the above technique of mass spectroscopy, the desorption of the particles of the analyte are realized by ionization of the analyte. However, in the case where the analyte is a material which is hard to evaporate (e.g., a biological material or the like), or a high-molecular-weight material such as a synthesized macromolecule, it is difficult to desorb the analyte. Therefore, various techniques enabling mass spectroscopy of the hard-to-evaporate materials and the high-molecular-weight materials have been studied. Nevertheless, the types and the molecular weight of the materials of which the mass spectroscopy can be performed are still limited.
The field-desorption mass spectroscopy (FD-MS), the fast-atom-bombardment mass spectroscopy (FAB-MS), the matrix-assisted laser desorption ionization (MALDI), and the like are currently known as techniques of mass spectroscopy for the hard-to-evaporate materials and the high-molecular-weight materials. Among others, the MALDI technique is known as a technique of mass spectroscopy which chemically affects the specimen to a relatively small degree, and enables measurement of analytes which have molecular weight exceeding ten thousand.
In the MALDI technique, a specimen is prepared by mixing an analyte in a matrix of sinapinic acid, glycerin, or the like, and is then irradiated with laser light so that the matrix absorbs the energy of the laser light and evaporates together with the analyte, and the analyte is ionized by proton transfer between the matrix and the analyte. Although, currently, use of the MALDI-TOF mass spectroscopy is widely spreading in the fields of biological materials and synthesized macromolecules, techniques for enabling more precise analysis in the MALDI-TOF mass spectroscopy have been studied, for example, as disclosed in Japanese Unexamined Patent Publication No. 9(1997)-320515.
In the MALDI-TOF mass spectroscopy, the matrix, as well as the analyte, is ionized, so that the matrix material also fly, is detected, and produces noise. Therefore, the sensitivity in the mass spectroscopy is likely to be lowered by the noise.
In addition, although the MALDI-TOF technique can be used in mass spectroscopy of the biological materials and synthesized macromolecules, high-energy laser light is necessary. Since the high-energy laser-light source is currently expensive, the use of the MALDI-TOF technique increases the equipment cost and therefore increases the measurement cost.